• Title, Summary, Keyword: Locking

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A Fast Lock and Low Jitter Phase Locked Loop with Locking Status Indicator (Locking 상태 표시기를 이용한 저잡음 고속 위상고정 루프)

  • Choi Young-Shig;Han Dae-Hyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.3
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    • pp.582-586
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    • 2005
  • This paper presents a new structure of Phase Locked Loop(PLL) which changes its loop bandwidth according to the locking status. The proposed PLL consists of a conventional PLL and, Locking Status Indicator(LSI). The LSI decides the operating bandwidth of loop filler. When the PLL becomes out of lock, the PLL increases the loop bandwidth and achieves fast locking. When the PLL becomes in-lock, this PLL decreases the loop bandwidth and minimizes phase noise output. The PLL can achieve fast locking and low phase noise output at the same time. Proposed PLL's locking time is less than $40{\mu}s$ and spur is 76.1dBc. It is simulated by HSPICE in a Hynix CMOS $0.35{\mu}m$ Process.

Selection of Valves Susceptible to Pressure Locking and Thermal Binding (압력잠김 및 열고착 현상 발생가능 밸브의 선정)

  • Lee, Sung-No;An, Jin-Geun;Kim, Seoug-Beom
    • The KSFM Journal of Fluid Machinery
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    • v.10 no.5
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    • pp.20-26
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    • 2007
  • Some gate valves are susceptible to pressure locking and thermal binding which prevent the safety function. The safety related gate valves susceptible to pressure locking and thermal binding shall be identified and taken preventive actions to ensure the safety function. The identification of the gate valves susceptible to pressure locking and thermal binding needs the evaluation of system design, valve and piping arrangement, test requirements, and operating conditions. Application of preventive methods should consider the system safety function, applicability, effectiveness, interface with system design, and cost. The selection procedure of valves susceptible to pressure locking and thermal binding can be effectively used in industry including nuclear power plants. In order to prevent the pressure locking, the hole can be drilled through the one disc of upstream side or down stream and the external equalizing line can be installed from bonnet to downstream or upstream. The double disc parallel seat valve type can be used instead of flexible wedge gate valve to prevent the thermal binding. The identification of gate valves susceptible to pressure locking and thermal binding, and preventive actions will meet the regulatory requirements and enhance the availability and safety of plants.

A Study on the Snap-Fit Locking Feature (스냅 핏 잠금 형상에 관한 연구)

  • Park, Hyun-Ki;Hong, Min-Sung
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.15 no.6
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    • pp.121-126
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    • 2006
  • Snap-fit is being used in manufacture of plastic products. Integral features using snap-fit are classified as locks, locators and enhancements. Locking features complete the process of attachment by providing physical interference to prevent separation. Looking feature pairs consist of two components, i.e., a flexible latch and a rigid catch and require particular care and attention for their selection. We can make several locking feature pairs by selecting latch and catch, but some parts restrict freedom of selection. Therefore, part designers must know the characteristic properties of generic locking feature forms as considering a specific design problem. In this paper, it has been presented about problem of small size products using locking feature and then introduced new locking feature applicable to small parts.

A technique to avoid aspect-ratio locking in QUAD8 element for extremely large aspect-ratios

  • Rajendran, S.
    • Structural Engineering and Mechanics
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    • v.37 no.6
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    • pp.633-648
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    • 2011
  • This paper investigates the aspect-ratio locking of the isoparametric 8-node quadrilateral (QUAD8) element. An important finding is that, if finite element solution is carried out with in exact arithmetic (i.e., with no truncation and round off errors), the locking tendency of the element is completely avoided even for aspect-ratios as high as 100000. The current finite element codes mostly use floating point arithmetic. Thus, they can only avoid this locking for aspect-ratios up to 100 or 1000. A novel method is proposed in the paper to avoid aspect-ratio locking in floating point computations. In this method, the offending terms of the strain-displacement matrix (i.e., $\mathbf{B}$-matrix) are multiplied by suitable scaling factors to avoid ill-conditioning of stiffness matrix. Numerical examples are presented to demonstrate the efficacy of the method. The examples reveal that aspect-ratio locking is avoided even for aspect-ratios as high as 100000.

An Analytical Study of Shear Locking (전단과대현상에 대한 해석적 고찰)

  • ;Ma, Haitao
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • pp.11-18
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    • 1993
  • An Analytical study of shear locking is introduced for linear thick beam element. The appropriate sampling point which eliminate shear locking phenomenon was Proposed through this study. Reduced integration point is exactly same as the sampling point obtained from this study. Numerical example indicates how shear locking is serious. some solutions for shear locking are presented.

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Analog Delay Locked Loop with Wide Locking Range

  • Yoo, Changsik
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.1 no.3
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    • pp.193-196
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    • 2001
  • For wide locking range, an analog delay locked loop (DLL) was designed with the selective phase inversion scheme and the variable number of delay elements. The number of delay elements was determined adaptively depending on the clock cycle time. During the analog fine locking stage, a self-initializing 3-state phase detector was used to avoid the initial state problem associated with the conventional 3-state phase detector. With these schemes, the locking range of analog DLL was increased by four times compared to the conventional scheme according to the simulation results.

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A Design of DLL(Delay-Locked-Loop) using new Locking Algorithm (새로운 Locking 알고리즘을 이용한 DLL(Delay-Locked-Loop) 설계)

  • 경영자;김태엽;이광희;손상희
    • Proceedings of the IEEK Conference
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    • pp.95-99
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    • 2000
  • New locking algorithm of DLL is proposed to improve the locking speed and low power dissipation in this paper, In spite of using the architecture of delay controller, low power consumption is acquired by operating only one controller at once and fast locking speed is accomplished by initial setting from the coarse controller. The proposed DLL circuit is operated from 50MHz to 200MHz and locked within 6 cycle at all of operating frequency.

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A Design of DLL(Delay-Locked-Loop) with Low Power & High Speed locking Algorithm (저전력과 고속 록킹 알고리즘을 갖는 DLL(Delay-Locked LooP) 설계)

  • 경영자;이광희;손상희
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.12C
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    • pp.255-260
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    • 2001
  • This paper describes the design of the Register Controlled DLL(Delay-Locked Loop) that achieves fast locking and low Power consumption using a new locking algorithm. A fashion for a fast locking speed is that controls the two controller in sequence. The up/down signal due to clock skew between a internal and a external clock in phase detector, first adjusts a large phase difference in coarse controller and then adjusts a small phase difference in fine controller. A way for a low power consumption is that only operates one controller at once. Moreover the proposed DLL shows better jitter performance Because using the lock indicator circuit. The proposed DLL circuit is operated from 50MHz to 200MHz by SPICE simulation. The estimated power dissipation is 15mA at 200MHz in 3.3V operation. The locking time is within 7 cycle at all of operating frequency.

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Clinical and Radiologic Outcomes of Acute Acromioclavicular Joint Dislocation: Comparison of Kirschner's Wire Transfixation and Locking Hook Plate Fixation

  • Rhee, Yong Girl;Park, Jung Gwan;Cho, Nam Su;Song, Wook Jae
    • Clinics in Shoulder and Elbow
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    • v.17 no.4
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    • pp.159-165
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    • 2014
  • Background: Kirschner's wire (K-wire) transfixation and locking hook plate fixation techniques are widely used in the treatment of acute acromioclavicular joint (ACJ) dislocation. The purpose of this study was to compare the clinical and radiologic outcomes between K-wires transfixation and a locking hook plate fixation technique. Methods: Seventy-seven patients with acute ACJ dislocation managed with K-wire (56 shoulders) and locking hook plate (21 shoulders) were enrolled for this study. The mean follow-up period was 61 months. Results: At the last follow-up, the shoulder rating scale of the University of California at Los Angeles (UCLA) was higher in patients treated with locking hook plate than with K-wires ($33.2{\pm}2.7$ vs. $31.3{\pm}3.4$, p=0.009). In radiologic assessments, coracoclavicular distance (CCD) (7.9 mm vs. 7.7 mm, p=0.269) and acromioclavicular distance (ACD) (3.0 mm vs. 1.9 mm, p=0.082) were not statistically different from contralateral unaffected shoulder in locking hook plate fixation group, but acromioclavicular interval (ACI) was significant difference. However, there were significant differences in ACI, CCD, and ACD in K-wire fixation group (p<0.001). Eleven complications (20%) occurred in K-wire transfixation group and 2 subacromial erosions on computed tomography scan occurred in locking hook plate fixation group. Conclusions: ACJ stabilization was achieved in acute ACJ dislocations treated with K-wires or locking hook plates. Locking hook plate can provide higher UCLA shoulder score than K-wire and maintain CCD, and ACD without ligament reconstruction. K-wire transfixation technique resulted in a higher complication rate than locking hook plate.

Development of a Concurrency Control Technique for Multiple Inheritance in Object-Oriented Databases (객체지향 데이터베이스의 다중계승을 위한 동시성 제어 기법 개발)

  • Jun, Woochun;Hong, Suk-Ki
    • Journal of Internet Computing and Services
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    • v.15 no.1
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    • pp.63-71
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    • 2014
  • Currently many non-traditional application areas such as artificial intelligence and web databases require advanced modeling power than the existing relational data model. In those application areas, object-oriented database (OODB) is better data model since an OODB can providemodeling power as grouping similar objects into class, and organizing all classes into a hierarchy where a subclass inherits all definitions from its superclasses. The purpose of this paper is to develop an OODB concurrency control scheme dealing with multiple inheritance. The proposed scheme, called Multiple Inheritance Implicit Locking (MIIL), is based on so-called implicit locking. In the proposed scheme, we eliminate redundant locks that are necessary in the existing implicit locking scheme. Intention locks are required as the existing implicit locking scheme. In this paper, it is shown that MIIL has less locking overhead than implicit locking does. We use only OODB inheritance hierarchies, single inheritance and multiple inheritance so that no additional overhead is necessary for reducing locking overhead.